Researchers at Albert Einstein College of Medicine, Yeshiva University, New York, USA, have shown, according to a press release, that football players who frequently head the ball have brain abnormalities resembling those found in patients with concussion (mild traumatic brain injury). The study, which used advanced imaging techniques and cognitive tests that assessed memory, was recently published online in the journal Radiology.
“We studied football players because football is the world’s most popular sport,” said Michael L Lipton, associate director of Einstein’s and medical director of MRI services at Montefiore, the University Hospital and academic medical center for Einstein. “Football is widely played by people of all ages and there is concern that heading the ball—a key component of the sport—might damage the brain,” he noted.
According to the press release, on average, football players head the ball six to 12 times during games, where balls can travel at speeds of more than 50 miles per hour. During practice drills, players commonly head the ball 30 or more times. The impact from a single heading is unlikely to cause traumatic brain damage such as laceration of nerve fibres. The cumulative damage from heading repeated subconcussive impacts might be clinically significant. “Repetitive heading could set off a cascade of responses that leads to degeneration of brain cells over time,” commented Lipton.
To study possible brain injury from heading, the researchers used diffusion tensor imaging (DTI), an advanced MRI-based imaging technique, on 37 amateur adult football players (median age 31 years) who had all played the sport since childhood. Participants reported playing football for an average of 22 years and had played an average of 10 months over the previous year. Researchers ranked the players based on heading frequency and then compared the DTI brain images of the most frequent headers with those of the remaining players. All participants also underwent cognitive testing.
“The DTI findings pertaining to the most frequent headers in our study showed white-matter abnormalities similar to what we have seen in patients with concussion,” said Lipton. “Football players who headed the ball above a threshold between 885 to 1,550 times a year had significantly lower FA in three areas of the temporal-occipital white matter.” Lipton noted that players with more than 1,800 headers per year were also more likely to demonstrate poorer memory scores compared to participants with fewer yearly headers.
“Our study provides compelling preliminary evidence that brain changes resembling mild traumatic brain injury are associated with frequently heading a soccer ball over many years,” said Lipton. “While further research is clearly needed, our findings suggest that controlling the amount of heading that people do may help prevent brain injury that frequent heading appears to cause.”